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•Green synthesis of Ag nanoparticles in a one-step using leaf extract of Kalanchoe Daigremontiana was performed.•Formation of Ag nanoflowers with different solvents was obtained.•Ag ...nanoflowers showed a high photocatalytic activity in the removal of methylene blue.•Ag nanoflowers showed high antibacterial activity against Escherichia coli, and Staphylococcus aureus bacteria.
The synthesis and applications of anisotropic nanostructures have attracted much attention in the last decade. The nanoflower-type structures are one of the nanomaterials with anisotropic structures most investigated because of owing to high densities of edges, corners, and stepped atoms present on their nano-petals. Here, silver nanoparticles obtained by a one-step green synthesis method using extract from Kalanchoe Daigremontiana´s leaves are reported. To identify the compounds responsible for reduction of silver ions, the functional groups present in plant extract were investigated by UV–vis and FTIR. Ag nanoparticles were characterized by UV–vis, XPS, ζ-potential, XRD, and SEM-EDS. Different solvents were used to eliminate agglomeration of the silver nanoparticles. These solvents produced nanoflower-like morphology with abundant nano-petals. This is the first report of the synthesis of Ag nanoflowers formed by green synthesis method using Kalanchoe Daigremontiana extract. The synthesized Ag nanoflowers are faced center cubic structure in nature with a petal thickness approximately of 25 nm. Photocatalytic activity of the different Ag nanostructures was evaluated through the degradation of methylene blue, where the degradation time as low as 1 min is reported. Furthermore these green synthesized Ag nanoflowers were found to show high antibacterial activity against Gram-negative bacteria Escherichia coli and Gram-positive Staphylococcus aureus.
Background: Excessive energy intake and obesity lead to the metabolic syndrome (MetS). Dietary saturated fatty acids (SFAs) may be particularly detrimental on insulin sensitivity (SI) and on other ...components of the MetS. Objective: This study determined the relative efficacy of reducing dietary SFA, by isoenergetic alteration of the quality and quantity of dietary fat, on risk factors associated with MetS. Design: A free-living, single-blinded dietary intervention study. Subjects and Methods: MetS subjects (n=417) from eight European countries completed the randomized dietary intervention study with four isoenergetic diets distinct in fat quantity and quality: high-SFA; high-monounsaturated fatty acids and two low-fat, high-complex carbohydrate (LFHCC) diets, supplemented with long chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs) (1.2 g per day) or placebo for 12 weeks. SI estimated from an intravenous glucose tolerance test (IVGTT) was the primary outcome measure. Lipid and inflammatory markers associated with MetS were also determined. Results: In weight-stable subjects, reducing dietary SFA intake had no effect on SI, total and low-density lipoprotein cholesterol concentration, inflammation or blood pressure in the entire cohort. The LFHCC n-3 PUFA diet reduced plasma triacylglycerol (TAG) and non-esterified fatty acid concentrations (P<0.01), particularly in men. Conclusion: There was no effect of reducing SFA on SI in weight-stable obese MetS subjects. LC n-3 PUFA supplementation, in association with a low-fat diet, improved TAG-related MetS risk profiles.
Polar lipids, especially glycerophospholipids, constitute the main components of cell membranes and are precursors of signaling molecules in many cellular and physiological processes. For this ...reason, the development of methods with high capability for detection of polar lipids in biological samples is required. In this research, the objective was to develop a method for comprehensive qualitative/quantitative determination of polar lipids in plasma by a combination of acquisition methods with a triple quadrupole mass analyzer. The strategy was optimized in two steps: (a) a first step for detection of lipids by monitoring selective fragmentation patterns representative of each lipid family and (b) a second step for confirmation of lipid species by detection and identification of product ions associated with the conjugated fatty acids. The acquisition list was divided into two multiple reaction monitoring (MRM) methods to ensure the detection of all transitions with suited instrumental sensitivity according to chromatographic retention time and relative abundance in plasma. The combination of the two MRM methods allowed the detection of 398 polar lipids in plasma in 64 min. Precision, estimated as within-day variability, was below 6.8% for all determined lipid families, while between-day variability was below 24.0%. This strategy has been applied to a cohort formed by 384 individuals in order to obtain a qualitative and quantitative distribution of polar lipids in human plasma. The most concentrated lipid families in relative terms were lysophospholipids, plasmalogens, and phosphatydilcholines, with mean relative concentration of 58.0, 17.1, and 8.3%, respectively. Then, sphingomyelins and phosphatidylethanolamines reported a relative concentration of 2.0%, followed by phosphatidylserines, with 1.1%.
Graphical abstract
The main limitations of lipidomics analysis are the chemical complexity of the lipids, the range of concentrations at which they exist, and the variety of samples usually analyzed. These limitations ...particularly affect the characterization of polar lipids owing to the interference of neutral lipids, essentially acylglycerides, which are at high concentration and suppress ionization of low concentrated lipids in mass spectrometry detection. The influence of sample preparation on lipidomics analysis of polar lipids in adipose tissue by LC–MS/MS was the aim of this research. Two common extractants used for lipids isolation, methanol:chloroform (MeOH:CHCl3) and methyl tert-butyl ether (MTBE), were qualitatively and quantitatively compared for the extraction of the main families of lipids. The obtained results showed that each family of lipids is influenced differently by the extractant used. However, as a general trend, the use of MTBE as extractant led to higher extraction efficiency for unsaturated fatty acids, glycerophospholipids and ceramides, while MeOH:CHCl3 favored the isolation of saturated fatty acids and plasmalogens. The implementation of a solid-phase extraction (SPE) step for selective isolation of glycerophospholipids prior to LC–MS/MS analysis was assayed to evaluate its influence on lipids detection coverage as compared to direct analysis. This step was critical to enhance the detection coverage of glycerophospholipids by removal of ionization suppression effects caused by acylglycerides.
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•Sample preparation has been studied in the analysis of polar lipids in adipose tissue.•The matrix used in this research was human visceral adipose tissue.•The study was performed by an untargeted LC–QTOF MS/MS approach.
The nuclear protein high-mobility group box 1 (HMGB1) can be passively released by necrotic cells or secreted actively by several cell types to regulate immune and inflammatory responses, as well as ...tissue remodeling. We herein aimed to characterize the effect of insulin resistance on HMGB1 in adipose tissue and to examine its potential role as a metabolic regulator in β-pancreatic cells.
Plasma HMGB1 concentration and adipose HMGB1 expression were assessed in relation to obesity and insulin resistance. Cultured adipocytes from lean and obese patients were used to investigate the intracellular distribution and factors regulating HMGB1 release, as well as to test its effects on adipogenesis and lipid metabolism. A regulatory role for HMGB1 in insulin secretion was also investigated.
Circulating HMGB1 was positively associated with body mass index, while adipose HMGB1 mRNA levels correlated with the expression of inflammatory markers. Insulin resistance modified the intracellular distribution of HMGB1 in human adipocytes, with HMGB1 being predominantly nuclear in lean and obese normoglycemic individuals while localized to the cytosol in obese patients with type 2 diabetes. Adipocytes from lean individuals exposed to conditioned media from lipopolysaccharide-stimulated macrophages induced HMGB1 redistribution to the cytoplasm and release. HMGB1 treatment had no effect on differentiation and lipid metabolism in adipocytes. However, HMGB1, whose circulating levels correlated with postload insulin concentration, increased both insulin release and intracellular Ca(2+) concentration in INS-1 cells.
These findings show, for the first time, that HMGB1 expression and release by human adipocytes is altered by inflammatory conditions as those imposed by obesity and insulin resistance. Our data reveal a novel role for HMGB1 as a stimulatory factor of insulin secretion of β-pancreatic cells.
Intermetallic phases with high aluminum content release hydrogen naturally; this is due to their susceptibility to hydrogen environmental embrittlement. Thus, in this work we take advantage of this ...phenomenon to assess hydrogen generation using the Fe2Al5 intermetallic that is mechanically activated. Furthermore, various aqueous solutions were evaluated by adjusting the pH with NaOH and CaO additions to increase both the rate and the amount of hydrogen generation. The Fe2Al5 intermetallic compound is useful material for the reaction with water and releases hydrogen. The results indicated that as the pH of the solution increases the amount and rate of hydrogen production increases. Reaction efficiency tends to be higher at pH = 13 with NaOH additive (near to 100%) being clearly better than CaO additive (35%). Small reaction capabilities with CaO additions are probably due to the CaO total consumption at the initial stages of the reaction, as the bayerite phase (reaction byproducts) is formed. At pH = 14, the NaOH addition reacts with iron, in addition to the reaction with aluminum particles, to achieve more than 100% reaction efficiency according to the presence of an iron oxyhydroxide phase identified by X-Ray diffraction.
•Ball-milling allows the intermetallic activation and the hydrogen generation reaction take place.•Aluminum from Fe2Al5 intermetallic reacts with aqueous solutions to release gas hydrogen.•The pH increase of the solution leads to hydrogen amount increase.
Abstract
Hysteresis loops exhibited by the thermal properties of undoped and 0.8 at.% W-doped nanocrystalline powders of VO
2
synthesized by means of the solution combustion method and compacted in ...pellets, are experimentally measured by photothermal radiometry. It is shown that: (i) the W doping reduces both the hysteresis loops of VO
2
and its transition temperature up to 15 °C. (ii) The thermal diffusivity decreases (increases) until (after) the metallic domains become dominant in the VO
2
insulating matrix, such that its variation across the metal-insulation transition is enhanced by 23.5% with W-0.8 at.% doping. By contrast, thermal conductivity (thermal effusivity) increases up to 45% (40%) as the metallic phase emerges in the VO
2
structure due to the insulator-to-metal transition, and it enhances up to 11% (25%) in the insulator state when the local rutile phase is induced by the tungsten doping. (iii) The characteristic peak of the VO
2
specific heat capacity is observed in both heating and cooling processes, such that the phase transition of the 0.8 at.% W-doped sample requires about 24% less thermal energy than the undoped one. (iv) The impact of the W doping on the four above-mentioned thermal properties of VO
2
mainly shows up in its insulator phase, as a result of the distortion of the local lattice induced by the electrons of tungsten. W doping at 0.8 at.% thus enhances the VO
2
capability to transport heat but diminishes its thermal switching efficiency.
In this investigation, silver nanoparticles having a size ranging from 5 to 40nm have been fast-biosynthesized by Tamarix gallica plant extract. The Ag nanoparticles obtained at room temperature by ...exposing the silver nitrate ions to the plant extract in an aqueous solution were characterized by UV–vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and scanning and transmission electron microscopy techniques. The biosynthesis process of spherical Ag nanoparticles exhibits a high rate of bioreduction being less than a 5min reaction. UV–vis spectroscopy shows a surface plasmon resonance band located at 426.7nm. The FT-IR spectrum of nanoparticles showed the presence of CO functional group that can be associated with the removal of aromatic compounds (benzenes) to form the nanometer solids. The antibacterial activity against Escherichia coli of silver nanoparticles synthesized with Tamarix gallica extract was confirmed.
•Tamarix gallica leaves extract was used to silver nanoparticles synthesis.•Studies by UV–vis spectroscopy confirmed the synthesis of silver nanoparticles and their evolution over the time.•FT-IR spectroscopy studies confirmed the organic compounds role in the reduction and stabilization of the Ag nanoparticles.•The Ag nanoparticles morphology is almost spherical with a size range of 5–40nm.•Silver nanoparticles showed antibacterial activity against E. coli.
Background
Smoking at the time of surgery is associated with postoperative complications. Quitting smoking before surgery is linked to fewer complications during the hospital stay. This work analysed ...whether a smoking cessation intervention before surgery is economically worthwhile when funded by the National Health System (NHS) in Spain.
Methods
The economic analysis considered costs and benefits of the intervention to the NHS for the year 2016. The population who would benefit comprised adult smokers who were ready to quit and for whom surgery requiring admission to hospital was planned. The intervention, a combination of medical counselling and use of a smoking cessation drug which should occur 12 weeks before surgery, considered one attempt only to quit smoking. Benefits were costs avoided by averting postoperative complications if cessation was successful. The analysis compared the net economic outcome (benefit minus cost of intervention) and the return on investment, for intervention funded by the NHS versus the current situation without funding.
Results
Smoking cessation increased by 21·7 per cent with funding; the rate was 32·5 per cent when funded versus 10·7 per cent without funding, producing 9611 extra quitters. The cost per averted smoker was €1753 with a benefit of €503, achieving a net economic benefit of €4·8 million per year. Given the annual cost of the intervention (€17·4 million, of which €5·6 million (32·5 per cent) represents drugs), the return on investment was 28·7 per cent annually, equivalent to €1·29 per €1 of investment.
Conclusion
From the perspective of the Spanish NHS, the benefit of funding smoking cessation before surgery, in terms of healthcare cost savings, appears to greatly outweigh the costs.
Antecedentes
Ser fumador activo hasta el momento de la cirugía se asocia con complicaciones postoperatorias. Se ha descrito una disminución de las complicaciones durante la hospitalización al abandonar el hábito de fumar antes de la cirugía. Este trabajo analizó si una intervención preoperatoria para dejar de fumar es económicamente beneficiosa cuando se financia por el Sistema Nacional de Salud (SNS) en España.
Métodos
En el análisis económico se consideraron tantos los costes como los beneficios de la intervención para el SNS, en euros, correspondientes al año 2016. La población que se beneficiaría eran fumadores adultos dispuestos a dejar de fumar, en los que se programase una intervención quirúrgica con hospitalización. La intervención, una combinación de asesoramiento médico y tratamiento farmacológico para dejar de fumar, se llevó a cabo a las 12 semanas antes de la cirugía, considerando únicamente un intento para dejar de fumar. Los beneficios fueron los costes evitados por una reducción en la tasa de complicaciones postoperatorias en los casos en los que se hubiese conseguido la eliminación del hábito. El análisis comparó el resultado económico neto (beneficio menos coste de la intervención) y el retorno de la inversión (return on investment, ROI), cuando la intervención era financiada por el SNS en comparación con la situación actual sin financiamiento público.
Resultados
La tasa de abandono del hábito tabáquico aumentó en un 21,8%; 32,5% cuando se financiaba frente al 10,7% sin financiación, consiguiendo un extra de 9.611 personas que dejaron de fumar. El coste por fumador rescatado fue de €1753 con un beneficio de €503, por lo que el beneficio económico neto conseguido fue de €4,8 millones por año. Dado que el coste anual de la intervención (€17,4 millones, de los cuales €5,6 millones corresponden a fármacos (32%)), el ROI anual fue del 28,7% con un beneficio de €1,29 por cada €1 de inversión.
Conclusión
Desde la perspectiva del SNS español, los beneficios de financiar el abandono del hábito de fumar en el preoperatorio de los pacientes, en términos de ahorro de costes parecen ser muy superiores a los costes de la intervención.
Smoking at the time of surgery is associated with postoperative complications. Quitting smoking before surgery is linked to fewer complications during the hospital stay. This work analysed whether a smoking cessation intervention before surgery is worthwhile economically when funded by the National Health System in Spain. The benefit of funding smoking cessation before surgery, in terms of healthcare cost savings, greatly outweighed the costs, with a substantial return on investment.
Benefits from funding smoking cessation
Ceramides are sphingolipids with a structural function in the cell membrane and are involved in cell differentiation, proliferation and apoptosis. Recently, these chemical species have been pointed ...out as potential biomarkers in different diseases, due to their abnormal levels in blood. In this research, we present an overall strategy combining data-independent and dependent acquisitions (DIA and DDA, respectively) for identification, confirmation, and quantitative determination of ceramides in human serum. By application of liquid chromatography-tandem mass spectrometry (LC-MS/MS) method in DIA mode we identified 49 ceramides including d18:1, d18:0, d18:2, d16:1, d17:1 and t18:0 species. Complementary, quantitative determination of ceramides was based on a high-throughput and fully automated method consisting of solid-phase extraction on-line coupled to LC-MS/MS in DDA to improve analytical features avoiding the errors associated to sample processing. Quantitation limits were at pg mL
level, the intra-day and between-days variability were below 20 and 25 %, respectively; and the accuracy, expressed as bias, was always within ±25 %. The proposed method was tested with the CORDIOPREV cohort in order to obtain a qualitative and quantitative profiling of ceramides in human serum. This characterization allowed identifying d18:1 ceramides as the most concentrated with 70.8% of total concentration followed by d18:2 and d18:0 with 13.0 % and 8.8 %, respectively. Less concentrated ceramides, d16:1, d17:1 and t18:0, reported a 7.1 % of the total content. Combination of DIA and DDA LC-MS/MS analysis enabled to profile qualitative and quantitatively ceramides in human serum.
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